Elapsed time indicator



Nov. 3, 1931.

F. B. LOVE ET AL ELAPSED TIME INDI CATOR Filed April 2, 1925 INVENTORDJraflc/s [3, Jew: and By Bo 4 72277 w v Q9 A TTORNE S Patented Nov. 3,1931 UNITED-STATES PATENT OFFICE FRANCIS B. LOVE AND IBOYID H. SMITH, OFSHELBY, OHIO, ASSIGNORS TO THE AUTO- 'CALL COMPANY, OF SHELBY, OHIO, ACORPORATION OF OHIO ELAPSED TIME INDICATOR Application filed April 2,

This invention relates to an elapsed time indicator. More particularlyit comprises mechanism, adapted to be associated with a signalingcircuit over which signals are arranged to be transmitted atpredetermined 1ntervals, which will sound an alarm or give othersuitable indication of the non-transmission of a signal within. the timeallotted over the supervised circuit. Heretofore in circuits includingwatchmans call-boxes and similar apparatus, it has been the practice toprovide recording apparatus at a central station to show when signalswere transmitted. Such records are usually made between the end ofbusiness hours of one day and the commencement of the following businessday, and the record made in the interval is inspected on the followingday, as a rule. In some instances central s ation supervision is made bya person detailed for such work. However, in most instances in smallcommunities or in industrial plants it is found impossible to providefor constant personal supervision at the recording station and yet thedangers of unsupervised systems are realized. Thus a watchman may becomeill or be physically disabled while making his rounds or may be cut offfrom his call-box by fire or some unforseen catastrophe and yetknowledge of the non-transmission of the signal may not reach thereserve station until after a time when relief could have been sent witha fair chance of protecting life and property.

The present invention has for its principal object the provision ofautomatic means which will supervise a signal transmitting circuit andwill give proper indications of the non-transmission of a single routinesignal upon the line under supervision during a predetermined timeinterval. Another object of the invention is to provide for a readilyadjustable means for varying the time interval during whichnon-transmission of a signal on the supervised line will result in aspecial signal or alarm. A further object of the invention is to providefor a series of signals or alarms to be transmitted in the event of thenon-transmission of a routine signal over thesupervised line, one suchalarm 1925. Serial No. 20,128.

being designed to reach a limited reserve station. such as the mainbuilding of an industrial plant, and the succeeding alarm, de signed tofollow the first alarm after a short time interval, such as two minutes,being of a more general character and being intended to notify thepolice or fire departments or sound a siren or other general alarmdevices. To the accomplishment of the foregoing and related ends, saidinvention, then, consists o1 the means hereinafter fully described andparticularly pointed out in the claims.

The annexed drawings and the following description set forth in detailcertain mechanism embodying the invention. such disclosed meansconstituting, however, but one of various mechanical forms in which theprinciple of the invention mav be used.

In said annexed drawings:

Fig. 1 is a front elevation of an apparatus embodying the principles ofour invention, with the cover portion thereof removed; Fig. 2 is avertical section view taken along the line 2-2 shown in Fig. 1, lookingin the direction of the arrows, the cover being shown in place; and Fig.3 is a sectional detailed view taken along the line 3+3 shown in Fig.1,-looking n the d rection of the arrows.

As is clearly shown in Figs. 1 and 2 of the drawings. the apparatuscomprises a casing having a supporting section -'1. and a cover section2. The supporting section comprises a base portion 3. and a back wall orpanel section 4. A rib 5 is provided in spaced relation to the edge ofthe panel section. with its lower portion 6 extending outwardly upon thebase section to p ovide a seat against wh ch the top 7 and side walls 8of the cover section may re t when the cover section is engaged inenclosing pos tion over the apparatus. A pair of studs 11 arescrew-threadedlv ensa qed in bosses 12 formed on the inner wall of thesupporting panel and the cover is provided with suitable apertures toreceive the free end of said studs. The outer ends of said studs arescrew-threaded and are adapted to be engaged bv wing nuts 13 which pressagainst the outer face of the cover and hold the same firmly against thesupporting panel. Adjacent the central lower portion of the panel uponthe inner side, a boss 14 of substantial area is formed. A screwthreadedaperture 15 is provided centrally of said boss within which a stud 16 isengaged. Said stud is provided with a shoulder above its screw-threadedportion adapted to bear against the forward faceof said boss andadjacent thereto is provided with a radial pin 17 over which the innerapertured lower end of a ratchet wheel return spring 18 is adapted to beengaged.

Upon the outer end of the stud 16 a ratchet wheel 21 is adapted to berotatably engaged. A retaining screw 22 is screw-threadedly engagedwithin a screw-threadedaxial opening formed in said stud and the head ofsaid retaining screw is adapted to bear against the outer face of anenlarged hub portion 23 formed on said ratchet wheel. Upon the innerface of saidratchet wheel a stud 24 is provided over which the outer endof the ratchet wheel return spring is adapted to be engaged. The ratchetteeth 25 on the outer periphery of the ratchet wheel are preferablvformed of small size in the form illustrated, one hundred teeth beingprovided. Adjacent the outer edge of the ratchet .wheel a series oftapped holes 26 is provided, said holes passing transversely throughsaid ratchet wheel and being equally spaced from each other. In the formillustrated, twenty ofsuchholesare provided. and an adjustable operatingscrew 27. provided with a sleeve of hakelite or other insulatingmaterial. is adapted to be engaged in one of said holes. The enlargedboss 14 formed on the inner face of the panel isprovided with a lateralextens on 29. having a screw-threaded aperture adapted to receivea stopscrew 31 pro jecting toward the inner face of the ratchet wheel. as'ismore clearly shown in Fig. 3 of thedrawings. Aistop screw 32 is adaptedto be secured in one of the tapped apertures of the ratchet wheel so asto project fromthe rearward face thereof and abut against the screw 31when said wheel is in its initial position.'being held thereagainstbvmcans of the action of the ratchet wheel return spring. Atthe-right-hand side of the ratchet wheel, as seen in Fig. 1, a step-upmagnet 33 is provided. Above said ratchet wheel a releasing magnet 34 isprovided. Said magnets are each provided .with laminated cores 35, 36,which are secured bv means of fasten ng screws 37, to lugs 38 formed atsuitable pointsupon the innerface of the supporting panel. The magnetwindings 41, 42. are

mounted upon the central arms of said mag net cores. Adjacent theforward end of the step-up magnet an armature arm 43 is provided, saidarm being pivoted upon a bearing screw 44 securedto the supportin panelad jacent the lower end of said step-up magnet, and extends verticallyadjacent sa d magnet poles to a .point slightly beyond the upper side ofsaid step-up magnet. The upper end of said armature arm is bifurcated soas to provide a pivotal support for the step-up latch 45 which issecured thereto by means of a pivot pin 46. The step-up latch isprovided on its under side at an intermediate point with a ratchet wheelengaging tooth 47, and extends at right angles to the armature arm 43and across the poles of the releasing magnet 34. "The rearward end ofsaid latch is adapted to bear against the end of an adjusting screw 48carried in a lug 49 projecting from the inner face of the supportingpanel, and a stop pin 50, secured to said panel, is adapted to beengaged by the adjacent outer face of said armature arm 43. A set screw51 serves to maintain said adjusting screw 48 in any desired position ofadjustment. Thus, by proper setting of the adjusting screw the degree ofmotion of the step-up latch may be accurately controlled and the properco-action of the tooth of said latch with the ratchet teeth may beprovided for. The free end of the step-up latch projects beyond the sideof the releasing magnet and is adapted to overl e a holding pawl 52mounted upon a bearing pin 53 set into the inner face of the supportingpanel. A coil. spring 54 is engaged over the outer end of said bearingpin and its ends are engaged respectively with said bearing pin and saidholding pawl so as to press the free end of the holding pawl downwardlyagainst the ratchet teeth. Upon the upper side of said holding pawl.spaced from the ratchet engaging end thereof, a headed in 55 isprovided, the shank of said pin being positioned within the narrowportion 56 of a key-hole slot formed through the outer portion of thestep-up latch. The engagement of said pin with said key-hole slot isbrought about by passing the head of said pin 55 through the enlargedportion of said key-hole slot and moving the same toward the pivoted endof said'latch. Thus, the step-up latch and pawl will be joined by a lostmotion connection, and upon the energization of the releasing magnet 34and the attraction of the step-up latch toward said magnet, said latchtooth will be withdrawn from the ratchet teeth, and after the body ofsaid latch strikes the under side of the head of said pin, the holdingpawl will also be lifted free of the ratchet teeth. Thus, the ratchetwheel will be free to return to its initial position through the actionof the ratchet wheel return spring.

Adjacent the lower portion of the support ing panel, extending frombeneath the ratchet wheel toward the lefthand side of the casing, aterminal block 61, preferably of bakelite or some similar material, isprovided, being secured to the rearward wall of the panel by means ofscrews 62 or similar fastening elements. A series-of binding posts 63 issupported upon said terminal block. Im-

mediately beneath said binding posts openings are provided through thebase plate for the circuit connections, and bakelite bushings 64 areinserted in said openings. The stepup magnet is connected with the tworighthand binding posts by means of electrical conductors 65, 66, andthe releasing magnet is connected by means of the conductor 67 with thebinding-post of the conductor 66, and by means of the conductor 68 to aseparate bind ing'post. The last two binding posts shown to the left areconnected by means of conductors 69, 70, with contact arms 71, 7 2,supported within a sectional insulating block 7 3 secured by means ofsuitable fastening elements to a supporting block 7 4: formed integrallywith the supporting panel. An intermediate contact arm 75 is provided,which is connected, through an intermediate binding post as shown, withthe power source and forms a part of an alarm circuit through either ofthe outer contact arms. \Vhen said intermediate arm is in contact withthe lower contact arm, the circuit will be established through apreliminary alarm circuit such as would ordinarily be found in the mainbuild ing of an industrial plant, and when said contact arm is movedagainst the upper contact, a circuit wil be closed through a generalalarm apparatus, such as would be installed in police or fireheadquarters or in the city hall of a small community. In many instancesit will be unnecessary to have a preliminary and a general alarm, as asingle warning signal, at a point where constant personal supervision ismaintained, will answer every requirement of security.

The forward end of the lower contact arm 71 is turned downwardly so asto provide a hook-shaped member 76 within which the insulating sleevecarried on the timing screw is adapted to engage. Immediately adjacentto said end of said contact arm contact point 77 is provided, said pointbeing in alignment with a similar contact point 78 formed on the underside of the intermediate switch arm 75. A similar contact point 79 isformed on the upper side of said intermediate switch arm and is adaptedto be moved into contact with a contact point 80 carried on the outerend of the upper contact arm 72, as is clearly shown in Figs. 1 and 3 ofthe drawings.

Transversely of the supporting block 7 4, a screw-threaded opening isprovided within which an adjusting screw 81 is adapted to be engaged.The end 82 of said adjusting screw adjacent the ratchet wheel, isprovided with a hole within which one end of the latch retracting spring83 is engaged. The opposite end of said latch retracting spring isadapted to be engaged over a pin 84L projecting inwardly from thestep-up latch at a central point thereof. Thus, any desired degree oftension upon the step-up latch may be provided for by turning theadjusting screw the necessary amount. A pair of lock nuts 85, 86, serveto maintain the adjustment of said adjusting screw.

The operation of the apparatus has been indicated in part in connectionwith the description of the construction of the various units. It mightbe pointed out, however, that the step-up magnet 33 is preferablyconnected by means of the two right-hand bind ing posts with conductorsleading to a master clock (not shown), and as said magnet is energizedat one minute intervals, the armature through the stepup latch willrotate the ratchet wheel one tooth for each minute impulse. The holdingpawl is spring pressed against the ratchet wheel and prevents the latterreturning to normal position as the step-up magnet is (lo-energized, andthe stepup latch is moved to its normal position by means of the latchretracting spring. Upon the succeeding energization of the step-upmagnet the ratchet wheel will be again ad vanced a tooth. Thus, theratchet wheel will be turned against the tension of the ratche wheelreturn spring and the adjustable operating screw 2? ill be moved in adirection toward the several spring contact arms. If at any time duringthe step-up movement of the ratchet wheel the releasing magnet isenergized, the step-up latch and the holding pawl will be withdrawnfro-1n the ratchet teeth and the ratchet wheel will be restored to itsinitial position by means of the ratchet wheel return spring. Theenergization of the releasing magnet is brought about through circuitconnection with the intermediate binding posts, which preferably extendto a relaying device (not shown) connected with the supervised circuit.If no such signal is transmitted over the super vised circuit, theinsulating sleeve on the adjustable operating screw 27 will be broughtinto contact with the lower switch arm and will move the same upwardlyinto contact with the adjacent contact arm, closing a circuit throughsaid arm to a preliminary sigaling device. If such preliminary signalresults in an investigation of the transmitting box from which theroutine signal should have been sent and the closing of the circuitthrough said box, the ratchet wheel will be restored to its initialposition. If, however, no su-en release of the ratchet wheel is broughtabout through the sending of the releasing signal over the circuit undersupervision, the ratchet wheel will continue to advance at one minuteintervals until the intermediate contact arm closes the circuit throughthe upper contact arm with the general alarm device heretofore referredto. When such general alarm is transmitted, those in charge of thesignaling system, or the police or fire departments in the community,will have been notified and the reason for the non-transmission of thesupervised circuit may be fully investigated.

The time interval during which asignal must be transmitted over thesupervised circuit depends upon the position of the adjustable operatingscrew 27 about the circumference of the ratchet wheel. The time intervalbetween the preliminary and general alarms where three contact arms areused, depends upon the space provided between the intermediate contactarm and the upper contact arm. It has been found that an interval of twominutes after the closing of the first pair of contacts is usuallysatisfactory prior to the sending in of a general alarm, but obviouslythe time interval may be varied as desired by spacing the intermediateand upper contact arms to the desired extent.

Other modes of applying the principle of our invention may be employedinstead of the one explained, change being made as regards the mechanismherein disclosed, irovided the means stated by any of the followingclaims or the equivalent of such stated means be employed.

lVe therefore particularly point out and distinctly claim as our ourinvention 1. An apparatus of the character described, having incombination a pair of spaced contact arms forming terminals of acircuit, a ratchet wheel, an adjustable operating screw carried by saidratchet wheel and adapted to be set in predetermined spaced relation tosaid contact arms and to be advanced toward a position to move said i.on'tact arms into circuit closing position, a spring for said ratchetwheel adapted to move said operating screw away from said contact arms,a pawl and latch engaging said ratchet wheel and adapted to move thesame progressively toward the point of engagement of the operating screwwith said contact arm, an electro-magnet, an armature for said magnetconnected with said latch for moving the same endwise and progressivelyrotating said ratchet wheel, a releasing electro-magnet adapted to atdirectly upon said latch, during the progressive advancement of saidscrew, to move the same transversely out of engagement with saidratchet, and a lost motion connection for said pawl and latch for movingsaid pawl free of said ratchet when said latch is moved transversely torelease said ratchet wheel and permit the screw to return to its initialposition without having operated said contact arms.

2-. An apparatus of the character desribed, having in combination a pairof spaced contact arms forming terminals of a circuit, a ratchet wheel,an adjustable operating screw carried by said ratchet wheel and adaptedto be set in predetermined spaced relation to said contact arms and tobe advanced toward a position to move said contact arms into circuitclosing position, a spring for said ratchet wheel adapted to move saidoperating screw away from said contact arms, a pawl and latch engagingsaid ratchet wheel and adapted to move the same progressively toward thepoint of engagement of the operating screw with said contact arm, anelectro-magnet, an armaure for said magnet connected with said latch formoving the same endwise and progressively rotating said ratchet wheel, apin "for limiting the motion of said armature toward said rat het wheel,an adjustable screw for limiting the motion of said armature toward saideleetro-magnet in rotating said ratchet wheel, a releasingelectro-magnot adapted to act directly upon said latch, during theprogressive advancement of said screw, to move the same transversely outof engagement with said ratchet, and a lost motion connection for saidpawl and latch for mov ng said pawl free of said ratchet when said latchis moved transversely to release said rachet wheel and permit the sameto return to its initial position without having operated said contatarms.

' 3 An apparatus of the character described, having in combination apair of spaced contact arms having contact points positioned adjacenttheir free ends, an intermediate contact arm disposed between said contat arms and having contact points on either side adapted to co-act withthe contact points on sai first-named arms to close independent crcuits. a ratchet wheel, an adjustable operating screw carried by saidratchet wheel and adapted to be set in predetermined spaced re aion tosaid (ontact arms and to be ad vanced toward a position to move saidcontact arms into circuit closing position, a spring for said ratchetwheel adapted to move said operating screw away from said contact arms,a pawl and latch engaging said ratchet wheel and adapted to move thesame progressively toward the point of engagement of the operating screwwith said contact arm, an electro-magnet, an armature for said magnetconnected with said latch for moving the same endwise and progressivelyrotating said ratchet wheel, a releasing electro-magnet adapted to actdirectly upon said latch, during the progressive advancement of saidscrew. to move the same transversely out of engagement with saidratchet. and a lost motion connection for said pawl and latch for movingsaid pawl free of said ratchet when said latch is moved transversely torelease said ratchet wheel and permit the same to return to its initialposition without having operated said contact arms.

4. An apparatus of the haracter described, having in combination threespaced contact arms forming terminals of two external circuits, aratchet wheel, an, adjustable operating screw carried by said ratchetwheel and adapted to be set in predetermined spaced relation to saidcontact arms and to be advanced toward a position to move said contactarms into circuit closing position, a spring for said ratchet wheeladapted to move said Operating screw away from said contact arms, a pawland latch engaging said ratchet wheel and adapted to move the sameprogressively toward the point of engagement of the operating screw withthe lowermost contact arm to move the same into contact with theintermediate arm to close the preliminary external circuit andthereafter to meve said intermediate contact arm into circuit closingposition with the upper contact arm to close the second externalcircuit, an electro-magnet, an armature for said magnet conneted withsaid latch for moving the same endwise and progressively rotating saidratchet wheel, a releasing electro-magnet adapted to act directly uponsaid latch, during the progressive advancement of said screw, to movethe same transversely out of engagement with said ratchet, and a lostmotion connection for said pawl and latch for moving said pawl free ofsaid ratchet when said latch is moved transversely to release saidratchet wheel and permit the same to return to its initial positionwithout having operated said contact arms.

5. An apparatus of the haracter described, having in combination threespaced contact arms forming terminals of two external circuits, aratchet wheel, an adjustable operating screw carried by said ratchetwheel and adapted to be set in predetermined spaced relation to saidcontact arms and to be advanced toward a position to move said contactarms into circuit closing position, a spring for said ratchet wheeladapted to move said operating screw away from said contact arms, a pawland latch engaging said ratchet wheel and adapted to move the sameprogressively toward the point of engagement of the operating screw withthe lowermost contact arm to move the same into contact with theintermediate arm to close the preliminary external circuit andthereafter to move said intermediate contact arm into circuit closingposition with the upper contact arm to close the second externalcircuit, an electro-magnet, an armature for said magnet connected withsaid latch for moving the same endwise and progressively rotating saidratchet wheel, a pin for limiting the motion of 4 said armature towardsaid ratchet wheel, an

adjustable screw for limiting the motion of said armature toward saidelectro-magnet in rotating said ratchet wheel. a releasingelectro-magnet adapted to act directly upon said latch, during theprogressive advancement of said screw, to move the same transversely outof engagement with said ratchet, and a lost mot-ion connection for saidpawl and latch for moving said pawl free of said ratlhet when said latchis moved transversely to release said ratchet wheel and permit the sameto return to its initial position without having operated said contactarms.

6. In a device of theclassdescribed, a disc, a pin adjustably mountedfor predetermined positioning on said disc and projecting therefrom, apair of switch arms mounted adjacent said disc and in the path of saidpin, means for progressively advancing said disc to carry said pintoward contact with said arms, resilient means resisting suchadvancement of said disc, and means freely operable at any stage of saidprogressive advancement of said disc for rendering said advancing meansinoperative.

7. In a device of the class described, a disc formed with a plurality ofspaced apertures adjacent its periphery, teeth on the periphery of saiddisc, a pin adapted to be selectively mounted in any one or saidapertures, a pair of switch arms mounted in the path of said pin, alatch cooperable with said teeth, means for moving said latchlongitudinally for progressively advancing said disc to carry said pintoward contact with said switch arms, resilient means for resisting saidadvance ment of said disc, a pawl cooperative with said teeth to holdsaid disc against movement in response to said resilient means, andmeans freely operable at any stage of said progressive advancement ofsaid disc for rendering said latch and pawl ineffective on said disc.

8. In a device of the class described, a disc formed with a plurality ofspaced apertures adjacent its periphery, teeth on the periphery of saiddisc, a pin adapted to be selectively mounted in any one of saidapertures, a pair of switch arms mounted in the path of said pin, alatch cooperable with said teeth, means for moving said latchlongitudinally for progressively advancing said disc to carry said pintoward contact with said switch arms, resilient means for resisting saidadvancement of said disc, a pawl cooperative with said teeth to holdsaid disc against movement in response to said resilient means, andmeans freely operable upon said latch at any stage of said progressiveadvancement of said disc for rendering said latch and pawl ineffectiveon said disc.

Signed by us, this 7th day of March. 1925.

FRANCIS B. LOVE. BOYD H. SMITH.

